Gripping and pushing device for medical instrument

ABSTRACT

In one representative embodiment, a gripping and pushing device for a medical instrument comprises an elongated main body defining a lumen. The elongated main body comprises one or more deflectable portions that can be pressed radially inwardly toward a shaft of the medical instrument extending through the lumen. One or more elastomeric gripping layers can be secured to the inner surface of a respective deflectable portion at axially spaced apart attachment locations. The one or more gripping layers are axially deformable relative to the one or more deflectable portions between the attachment locations when manual pressure is applied to the one or more deflectable portions to press the one or more gripping layers against the shaft and move the shaft longitudinally into a patient&#39;s body.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of, and incorporates by reference,U.S. Provisional Patent Application Ser. No. 62/205,567, filed Aug. 14,2015.

FIELD

This invention relates generally to embodiments of a gripping andpushing device for inserting a medical instrument, such as a catheter,into a patient's body.

BACKGROUND

Elongated medical instruments are inserted into a patient's body toperform a wide variety of procedures. Catheters, for example, are ofteninserted into a subject to drain fluids, or used to deliver and implanta medical device, such as a stent or a prosthetic valve, at a locationinside a subject. Cardiac catheterization, such as for performingangioplasty or implanting a prosthetic heart valve, can involve the useof a relatively long catheter that is advanced through a patient'svasculature to access the heart. In one approach, for example, thecatheter can be advanced through a femoral artery and the aorta toaccess the heart.

Control and advancement of catheters, especially for cardiaccatheterization, is difficult because of their construction. The usermust frequently manipulate, or torque, the catheter shaft on theproximal end to facilitate advancement of the catheter with a desiredorientation on the distal end. To provide the needed control over themovement of the catheter, it is necessary that these tubular cathetersbe made somewhat rigid. However, catheters must be flexible enough tonavigate through the body lumen to arrive at the desired location withinthe body where the medical procedures will be performed. An overly rigidcatheter shaft will not easily track, or follow, a guidewire. Because oftheir length, it is often necessary for the practitioner to grasp therelatively narrow shaft of the catheter at a location near the entrypoint into the patient's vasculature rather than the handle at the veryproximal end of the catheter to avoid buckling of the shaft.Unfortunately, it is often difficult to obtain and maintain a sure gripon the relatively narrow shaft for the necessary control and graspingthe shaft with a tight grip causes user fatigue.

Therefore, what has been needed is a device that improves apractitioner's ability to insert and control advancement of a medicalinstrument through a patient's body.

SUMMARY

The present disclosure is directed to embodiments of a gripping andpushing device for use with a medical instrument that is insertable intoa patient's body. In particular embodiments, the gripping and pushingdevice is placed on a relatively narrow, elongated structure of themedical instrument, such as a shaft or tubular member. Instead ofgripping the shaft directly, a practitioner can squeeze or grip thegripping and pushing device, which in turn grips the medical instrumentand transfers pushing, pulling and/or rotational motion of thepractitioner's hand to the shaft. The gripping and pushing deviceprovides a larger gripping area for the practitioner to allow thepractitioner to maintain a better grip and control over the medicalinstrument with less fatigue as the medical instrument is pushed intothe patient's body, torqued, or otherwise manipulated within thepatient's body.

To enhance the gripping force of the device against the shaft of themedical instrument, the device can include at least one gripping layersecured to an inner surface of a deflectable portion of the device.Gripping the deflectable portion causes the deflectable portion todeflect radially inwardly toward the shaft and press the gripping layeragainst the shaft. The gripping layer can be formed from a materialhaving a greater coefficient of friction than the deflectable portion.In particular embodiments, the gripping layer is secured to the innersurface of the deflectable portion at axially spaced apart attachmentlocations (such as with a suitable adhesive) so as to define unsecuredportions between the attachment locations. The unsecured portions of thegripping layer are axially deformable. Thus, when gripping and pushingforces are applied to the device, the unsecured portions can “bunch up”or form non-linear segments that further enhance the effective grippingforce of the gripping layer against the shaft.

In one representative embodiment, a gripping and pushing device for amedical instrument comprises an elongated main body defining a lumen.The elongated main body comprises one or more deflectable portions thatcan be pressed radially inwardly toward a shaft of the medicalinstrument extending through the lumen. One or more elastomeric grippinglayers can be secured to the inner surface of a respective deflectableportion at axially spaced apart attachment locations. The one or moregripping layers are axially deformable relative to the one or moredeflectable portions between the attachment locations when manualpressure is applied to the one or more deflectable portions to press theone or more gripping layers against the shaft and move the shaftlongitudinally into a patient's body.

In another representative embodiment, a method of inserting a medicalinstrument into the body of a patient comprises gripping a gripping andpushing device disposed on a shaft of the medical instrument. Thegripping and pushing device comprises at least one elongated deflectableportion and at least one gripping layer secured to an inner surface ofthe deflectable portion at axially spaced attachment locations, whereingripping the gripping and pushing device causes the deflectable portionto deflect toward the shaft and press the gripping layer against theshaft. While gripping the gripping and pushing device, the gripping andpushing device is pushed toward the patient to advance the medicalinstrument into the patient's body.

In another representative embodiment, a medical assembly comprises adelivery apparatus for delivering a prosthetic device into a patient'sbody. The delivery apparatus comprises a handle and an elongated shaftextending from the handle. The assembly further comprises a gripping andpushing device disposed on the shaft of the delivery apparatus. Thegripping and pushing device comprises an elongated main body defining alumen through which the shaft extends. The elongated main body comprisesat least one deflectable portion and at least one gripping layer securedto an inner surface of the deflectable portion at axially spaced apartattachment locations so as to define one or more unsecured portions ofthe gripping layers between the attachment locations. The deflectableportion is deflectable from a non-deflected position with the grippinglayer radially spaced from the shaft and a deflected position with thegripping layer engaging the shaft.

The foregoing and other objects, features, and advantages of theinvention will become more apparent from the following detaileddescription, which proceeds with reference to the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation view of a delivery system for delivering aprosthetic device into a patient's body, showing a catheter gripping andpushing device disposed on a shaft of a delivery catheter of the system.

FIG. 2 is a perspective view of the catheter gripping and pushing deviceof FIG. 1.

FIG. 3 is a cross-sectional view of the catheter gripping and pushingdevice taken along line 3-3 of FIG. 2.

FIG. 4A is a cross-sectional view of the catheter gripping and pushingdevice of FIG. 1 taken along a plane extending lengthwise of thegripping and pushing device, showing the gripping and pushing device ina relaxed, non-use position.

FIG. 4B is a cross-sectional view of the catheter gripping and pushingdevice similar to FIG. 4A but showing the gripping and pushing devicebeing used to grip and push the shaft of the delivery catheter into thepatient's body.

FIG. 5A is a side elevation view of the catheter gripping and pushingdevice of FIG. 1 shown in a relaxed, non-use position.

FIG. 5B is a side elevation view of the catheter gripping and pushingdevice of FIG. 1 shown being used to grip the shaft of the deliverycatheter.

FIG. 6 is a side elevation view of the catheter gripping and pushingdevice of FIG. 1, showing the opposite side the device from the viewshown in FIG. 5B.

DETAILED DESCRIPTION

For purposes of this description, certain aspects, advantages, and novelfeatures of the embodiments of this disclosure are described herein. Thepresent disclosure is directed toward all novel and nonobvious featuresand aspects of the various disclosed embodiments, alone and in variouscombinations and sub-combinations with one another. The methods,apparatuses, and systems are not limited to any specific aspect orfeature or combination thereof, nor do the disclosed embodiments requirethat any one or more specific advantages be present or problems besolved.

Features, integers, characteristics, compounds, chemical moieties orgroups described in conjunction with a particular aspect, embodiment orexample of the invention are to be understood to be applicable to anyother aspect, embodiment or example described herein unless incompatibletherewith. All of the features disclosed in this specification(including any accompanying claims, abstract and drawings), and/or allof the steps of any method or process so disclosed, may be combined inany combination, except combinations where at least some of suchfeatures and/or steps are mutually exclusive. The invention is notrestricted to the details of any foregoing embodiments. The inventionextends to any novel one, or any novel combination, of the featuresdisclosed in this specification (including any accompanying claims,abstract and drawings), or to any novel one, or any novel combination,of the steps of any method or process so disclosed.

Although the operations of some of the disclosed methods are describedin a particular, sequential order for convenient presentation, it shouldbe understood that this manner of description encompasses rearrangement,unless a particular ordering is required by specific language. Forexample, operations described sequentially may in some cases berearranged or performed concurrently. Moreover, for the sake ofsimplicity, the attached figures may not show the various ways in whichthe disclosed methods can be used in conjunction with other methods. Asused herein, the terms “a”, “an”, and “at least one” encompass one ormore of the specified element. That is, if two of a particular elementare present, one of these elements is also present and thus “an” elementis present. The terms “a plurality of” and “plural” mean two or more ofthe specified element.

As used herein, the term “and/or” used between the last two of a list ofelements means any one or more of the listed elements. For example, thephrase “A, B, and/or C” means “A”, “B,”, “C”, “A and B”, “A and C”, “Band C”, or “A, B, and C.”

As used herein, the term “coupled” generally means physically coupled orlinked and does not exclude the presence of intermediate elementsbetween the coupled items absent specific contrary language.

The present disclosure is directed to embodiments of a gripping andpushing device for use with a medical instrument that is insertable intoa patient's body. The illustrated embodiment is described in the contextof inserting a delivery apparatus or catheter into a patient'svasculature. However, it should be understood that the embodimentsdisclosed herein can be used with any of various medical instruments toperform any of various medical procedures, such as administration ofmedication or fluids, implantation of prosthetic devices, drainage offluids, to name a few examples. Some examples of medical instruments(other than catheters) that can be used with the disclosed embodimentsinclude but are not limited to, needles, stylets, cannulas, endoscopicdevices, laparoscopic instruments, and/or combinations thereof.

In general, the gripping and pushing device is placed on a relativelynarrow, elongated structure of the medical instrument, such as a shaftor tubular member. Instead of gripping the shaft directly, apractitioner can squeeze or grip the gripping and pushing device, whichin turn grips the medical instrument and transfers pushing, pullingand/or rotational motion of the practitioner's hand to the shaft. Thegripping and pushing device provides a larger gripping area for thepractitioner to allow the practitioner to maintain a better grip andcontrol over the medical instrument with less fatigue. This can beespecially helpful when the practitioner is wearing gloves made fromlatex or other polymers, the outer surface of which can become slipperyif covered in blood, saline, or other fluid.

FIG. 1 shows a delivery system 100 for a delivering a prosthetic device(e.g., a prosthetic valve or stent) into the body of a patient. Thedelivery system 100 can include a delivery apparatus (also referred toas a delivery catheter) 102 and an introducer 104. The deliveryapparatus 102 can include a handle 106 and an elongated shaft 108extending distally from the handle 106. An implantable prosthetic device(e.g., a prosthetic valve or stent) (not shown) can be mounted in acompressed state on a distal end portion of the shaft 108 for deliveryinto the patient's body.

The shaft 108 can be sized and shaped to be advanced through thepatient's vasculature to a desired implantation site for the prostheticdevice. For example, for delivering a prosthetic heart valve in atransfemoral procedure, the shaft 108 is pushed through a femoral arteryand the aorta in a retrograde direction to access the heart. In anothertransfemoral procedure, the shaft 108 is pushed through a femoral veinand the inferior vena cava in an antegrade direction to access theheart. For transfemoral delivery of a prosthetic valve to the heart, theshaft 108 can have a length of 48 inches or longer.

The introducer 104 can include a housing 110 and an elongated sheath 112extending distally from the housing 110. In use, the sheath 112 can beinserted first into the access location of the patient's vasculature(e.g., a surgical cut down of a femoral artery) and the shaft 108 of thedelivery apparatus 102 can then be inserted through the introducer 104and into the patient's vasculature. The housing 110 can have one or moreseals (not shown) that can engage the shaft 108 and therefore minimizeblood loss during the procedure. The introducer 104 facilitates theinitial introduction of the delivery apparatus into the vasculature andcan protect against trauma to the vessel where the delivery apparatus isinserted. In some applications, however, the delivery apparatus 102 maybe inserted directly into the patient's vasculature without the use ofthe introducer 104. Further details of the delivery apparatus 102 andthe introducer 104 are described in U.S. Patent Application Publication2013/0030519, which is incorporated herein by reference.

As further shown in FIG. 1, a catheter gripping and pushing device 200,according to one embodiment, is mounted on the shaft 108 of the deliveryapparatus 102 and can be used for manipulating the shaft 108, such asfor pushing the shaft into the patient's vasculature (e.g., a femoralartery and the aorta) and/or torqueing the shaft to effect steering orplacement of the prosthetic device within the body. It should beunderstood that the gripping and pushing device 200 could be used in avariety of other applications for pushing and/or manipulating cathetersand other medical instruments within various parts of the body and isnot limited for use with a delivery apparatus for delivering aprosthetic device.

As best shown in FIGS. 2 and 3, the pushing device 200 in theillustrated embodiment comprises an elongated main body 202 mounted onand extending from an inner tube or shaft 218. The body 202 defines alumen 204 and can be formed with first and second longitudinallyextending slots 206, 208, respectively on opposite sides of the body,thereby defining two elongated, deflectable portions, such as in theform of diametrically opposed legs 210, 212. The first slot 206 canextend the entire length of the body 202 (FIG. 5A), while the secondslot 208 can be a partial slot extending less than the entire length ofthe body 202. For example, the second slot 208 can extend from theproximal end of the body 202 to a location at the proximal end of theinner tube 218 (FIG. 6). A distal end portion 222 of the body 202 issecured to the inner tube 218 (e.g., with a suitable adhesive) such thatthe legs 210, 212 are cantilevered from the inner tube 218 and can bepressed inwardly toward each other and against the shaft during use, asfurther described below.

Although in the illustrated embodiment the pushing device includes twoslots 206, 208 and two legs 210, 212, the pushing device can be formedwith any number of slots and legs in alternative embodiments. In otherembodiments, the body 202 need not be formed with separate legs 210, 212but is otherwise deformable or deflectable to allow opposing portions ofthe body 202 to be pressed against the shaft 108 during use. In oneimplementation, for example, the main body can have a substantiallyC-shaped cross-section (in a plane perpendicular to the length of themain body) defining one slot extending partially or along the entirelength of the main body, wherein opposing sides of the main body aredeflectable and can be pressed against the shaft 108 during use. Inanother implementation, the main body can have a substantially circularcross-section without any slots (or another closed annular shape) and issufficiently flexible to allow opposing sides of the main body to bepressed inwardly against the shaft 108.

The inner tube 218 can be formed with a longitudinal slit 220 that isaligned with the first slot 206. In this manner, the pushing device 200can be placed on the shaft 108 from the side by pushing the shaft 108laterally through the first slot 206 and the slit 220 such that theshaft 108 extends co-axially through the inner tube 218 and the lumen204 of the body. Conversely, the pushing device 200 can be removed theshaft 108 by simply by pulling the pushing device 200 laterally awayfrom the shaft 108 so that the shaft 108 slides through the slit 220 andthe first slot 206. In other embodiments, the inner tube 218 need not beformed with a slit 220, in which case the pushing device 200 would beplaced on the shaft 108 by threading an end of the shaft co-axiallythrough the inner tube 218.

Secured to the inner surface of each leg 210, 212 is an inner grippinglayer, or gripping strip, 214. As best shown in FIG. 4A, each grippinglayer 214 can be secured to a respective leg 210, 212 by one or moreaxially spaced-apart attachment locations, such as the illustratedadhesive spots 216, defining unsecured portions 224 of the layers 214between the attachment locations that are unattached to the innersurfaces of the legs 210, 212. The unsecured portions 224 can deformunder manual pressure of user pressing against the legs 210, 212 toenhance the gripping action of the layers 214, as further describedbelow. The thickness of the adhesive spots 216 shown in FIGS. 4A and 4Bare exaggerated for purposes of illustration. In lieu of or in additionto the use of an adhesive, other techniques and/or mechanisms can beused to secure the gripping layers 214 to the legs 210, 212 atspaced-apart attachment locations, such as but not limited to, thermalwelding, mechanical fasteners, and/or combinations thereof.

As best shown in FIG. 2, each gripper layer 214 in the illustratedembodiment is secured to a respective leg 210, 212 at three spaced-apartattachment locations by three spaced-apart adhesive spots 216. Inalternative embodiments, each gripping layer 214 can be secured to arespective leg 210, 212 at greater than or fewer than three attachmentlocations. The adhesive spots 216 are separate layers of an adhesivedisposed between the inner surface of the legs 210, 212 and the outersurface of the gripping layers 214 and can have any of various shapes(e.g., circular, elliptical, etc.). The adhesive spots 216 can beequally spaced from each other as shown in the drawings. Alternatively,the spacing between adjacent adhesive spots 216 can vary along thelength the pushing device. Also, the spacing and/or positioning of theadhesive spots 216 of one gripping layer 214 can be different than thespacing and/or positioning of the adhesive spots of another grippinglayer 214. In other embodiments, additional gripping layers 214 can besecured to each other at spaced apart attachment locations. For example,multiple gripping layers can be secured to the inner surface of one orboth legs 210, 212 with adjacent gripping layers being secured to eachother at spaced apart attachment locations.

Referring to FIGS. 4A and 4B, the inner tube 218 has a lumen 230 sizedand shaped to receive the shaft 108. The diameter of the lumen 230 canbe slightly greater than the diameter of the shaft 108 to allow thepushing device 200 to slide along the length of the shaft 108. The lumen204 of the body 202 is oversized relative to the shaft 108, which allowsthe legs 210, 212 to move between a non-deflected state in which thelegs are spaced apart from the shaft 108 (FIGS. 4A and 5A) and adeflected state in which the legs are pressed against the shaft 108 bymanual pressure from a user's hand (FIGS. 4B and 5B).

The body 202 desirably comprises a material with sufficient flexibilityand/or elasticity to be easily compressed under manual pressure allowingthe internal gripping layers 214 to contact the shaft 108 when grippingpressure is applied and revert back to the non-deflected state under itsown resiliency when gripping pressure is released. Any of varioussuitable materials, such as any of various metals (e.g., stainlesssteel) or polymeric materials can be used to form the body 202, such asbut not limited to Nylon, Pebax, and/or combinations thereof. The legs210, 212 can have roughened or textured inner and outer surfaces toenhance adherence with the gripping layers 214 and improve gripping by auser's hand. The inner gripping layers 214 desirably comprise anelastomeric material that can deform when manual pressure is applied tothe legs 210, 212. In some embodiments, the gripping layers 214 areformed from a material that is relatively more elastic and/or deformablethan the legs 210, 212 and has a relatively greater coefficient offriction with respect to the shaft 108 than the legs and a relativelylow shore A hardness. Any of various suitable elastomers can be used forforming the gripping layers 214 such as, for example, low hardnesssilicone rubber.

The inner tube 218 can be made from any of various suitable materials,such as any of various polymeric materials, such as but not limited toNylon, Pebax, PTFE, and/or combinations thereof. In some embodiments,the inner tube 218 can be made from a low-friction material and can havea relatively low coefficient of friction with respect to the shaft 108compared to the gripping layers 214 to promote sliding of the pushingdevice 200 relative to the shaft when the legs 210, 212 are not incontact with the shaft. In some embodiments, the inner tube 218 caninclude an inner liner or layer of low friction material, such as PTFE,to reduce sliding friction with the shaft 108.

In some embodiments, the outer surface of the body 202 can be providedwith gripping layers (not shown) similar to gripping layers 214 toenhance a user's grip on the body 202. For example, elongated grippinglayers can be placed along the outer surface of the legs 210, 212 inalignment with the gripping layers 214. The gripping layers on the outersurface of the body can be formed from the same materials as thegripping layers 214 (e.g., silicone rubber).

In use, the pushing device 200 is placed on the shaft 108 of thedelivery apparatus 102 as shown in FIG. 1. In many applications, such asin procedures for implanting prosthetic heart valves, the shaft 108 canbe several feet long and is relatively flexible. Consequently, thephysician may need to grasp the shaft 108 close to the insertion pointof the patient's body and away from the handle 106 while pushing theshaft into the body to prevent buckling of the shaft. Thus, the pushingdevice 200 can be initially positioned along the shaft 108 at a desireddistance from the entry point and the introducer 104 (if used), such asa few inches from the entry point.

The legs 210, 212 of the pushing device 200 can then be squeezed betweenthe fingers 228 (e.g., a thumb and an index finger) to press thegripping layers 214 against the shaft 108. While maintaining manualpressure against the legs 210, 212, the pushing device 200 is advanceddistally in the direction of arrows 232, which pushes the shaft 108through the introducer 104 and into the patient's vasculature. Asillustrated in FIG. 4B, the unsecured portions 224 of the grippinglayers 214 between the adhesive spots 216 are axially deformable, andcan bunch up and/or or stretch or deform axially, forming wave-likedeformations that enhance the gripping force against the shaft 108 andminimize slippage of the gripping device relative to the shaft. Thus,the deformation of the gripping layers 214 allow the physician to pushthe shaft 108 through the patient's vasculature with less manual force,thereby reducing finger fatigue and enhancing control over the shaft108.

After the pushing device 200 has been moved distally to a location atthe introducer 104 (which is effective to insert the shaft 108 partiallyinto the patient's vasculature), manual pressure can be released fromthe legs 210, 212 (which can revert back to their non-deflected state),and the pushing device 200 can be slid proximally relative to the shaft108 and away from the patient a desired distance, such as by graspingthe inner tube 218 or the distal end portion 222 of the body andretracting the pushing device relative to the shaft. Thereafter, thephysician can again grasp the legs 210, 212 and use the pushing device200 to push the shaft 108 further into the patient's vasculature. Theprocess of retracting the pushing device and using the pushing device topush the shaft further into the patient's body can be repeated as neededuntil the handle 106 can be effectively used to push or otherwisemanipulate the shaft without buckling.

In view of the many possible embodiments to which the principles of thedisclosed invention may be applied, it should be recognized that theillustrated embodiments are only preferred examples of the invention andshould not be taken as limiting the scope of the invention. Rather, thescope of the invention is defined by the following claims. We thereforeclaim as our invention all that comes within the scope and spirit ofthese claims.

I claim:
 1. A gripping and pushing device for a medical instrumentcomprising: an elongated main body defining a lumen, the elongated bodycomprising one or more deflectable portions that can be pressed radiallyinwardly toward a shaft of the medical instrument extending through thelumen, each deflectable portion having an inner surface; one or moreelastomeric gripping layers, each secured to the inner surface of arespective deflectable portion at axially spaced apart attachmentlocations; wherein the one or more gripping layers are axiallydeformable relative to the one or more deflectable portions between theattachment locations when manual pressure is applied to the one or moredeflectable portions to press the one or more gripping layers againstthe shaft and move the shaft longitudinally into a patient's body;wherein the gripping and pushing device further comprising an innertubular member and wherein the main body comprises an end portionmounted on the inner tubular member such that the deflectable portionsare cantilevered from the inner tubular member.
 2. The gripping andpushing device of claim 1, in combination with the medical instrument.3. The gripping and pushing device of claim 1, in combination with themedical instrument, wherein the medical instrument comprises a deliveryapparatus for delivering and implanting a prosthetic device within thepatient's body.
 4. The gripping and pushing device of claim 1, whereinthe one or more deflectable portions comprise first and seconddiametrically opposed leg portions, and the one or more gripping layerscomprise first and second diametrically opposed gripping layers securedto the first and second leg portions, respectively.
 5. The gripping andpushing device of claim 1, wherein portions of the one or more grippinglayers between the attachment locations are stretchable relative to theone or more deflectable portions.
 6. The gripping and pushing device ofclaim 1, wherein the device is split longitudinally along its entirelength to permit placement on the shaft laterally from one side of theshaft.
 7. The gripping and pushing device of claim 1, wherein the mainbody comprises a first material and the gripping layers comprise asecond material, the second material having a higher coefficient offriction that the first material.
 8. The gripping and pushing device ofclaim 1, wherein the gripping layers comprise an elastomer.
 9. Thegripping and pushing device of claim 1, wherein the one or more grippinglayers are adhered to the one or more deflectable portions with adhesivespots at the axially spaced apart attachment points.
 10. The grippingand pushing device of claim 1, wherein the one or more gripping layersare welded to the one or more deflectable portions at the axially spacedapart attachment points.